S B Stinton1, P L Graham2, N A Moloney3, L R Maclachlan4, D W Edgar5, E Pappas6. 1. Arthritis and Musculoskeletal Research Group, The University of Sydney, 75 East St, O204, Lidcombe NSW 2141, Australia, and Westmead Private Physiotherapy Services, 16 Mons Rd, Westmead NSW 2145, Australia. 2. Macquarie University, 12 Wally's Walk, Building E7A, Level 6, Macquarie University, NSW 2109, Australia. 3. Macquarie University, 75 Talavera Road, Macquarie Park, NSW 2113, Australia. 4. School of Health and Rehabilitation Sciences, The University of Queensland, St Lucia QLD 4072, Australia. 5. Fiona Stanley Hospital, Fiona Wood Foundation and The University of Notre Dame Australia, 11 Robin Warren Drive, Murdoch, WA 6150, Australia, Fiona Wood Foundation, 102-118 Murdoch Drive, Murdoch, WA 6150, Australia, and The University of Notre Dame Australia, 19 Mouat Street, Fremantle WA 6160, Australia. 6. Arthritis and Musculoskeletal Research Group, The University of Sydney, 75 East St, O204, Lidcombe NSW 2141, Australia.